Comment # 6 on bug 1212835 from Michal Suchanek

(In reply to Petr Tesařík from comment #4)
> Installation is not an issue. There is a symbolic link from /lib to
> /usr/lib. All we need is to create a similar link in scripts/depmod.sh.
> Something like this:
> 
> --- a/scripts/depmod.sh
> +++ b/scripts/depmod.sh
> @@ -27,7 +27,8 @@ fi
>  # numbers, so we cheat with a symlink here
>  depmod_hack_needed=true
>  tmp_dir=$(mktemp -d ${TMPDIR:-/tmp}/depmod.XXXXXX)
> -mkdir -p "$tmp_dir/lib/modules/$KERNELRELEASE"
> +mkdir -p "$tmp_dir/usr/lib/modules/$KERNELRELEASE"
> +ln -s usr/lib "$tmp_dir/lib"
>  if "$DEPMOD" -b "$tmp_dir" $KERNELRELEASE 2>/dev/null; then
>  	if test -e "$tmp_dir/lib/modules/$KERNELRELEASE/modules.dep" -o \
>  		-e "$tmp_dir/lib/modules/$KERNELRELEASE/modules.dep.bin"; then

That papers over the problem in the case the modules are not installed.

Nonetheless, for upstreamable patch the aim should be to support installing
modules under an arbitrary prefix. Probably the prefix should be queried from
kmod because kmod supports only one prefix, and the kernel needs to use that
one supported prefix.